The effect of acute changes in blood flow on local lymph flow in the limbs of anesthetized sheep

A study was made of the effects of acute changes in local blood flow on lymph flow in the feet of anesthetized sheep. Lymph outflow pressure and flow and venous pressure were measured in cannulated vessels draining the foot region. Local volume changes were also measured. Acute reductions in blood flow were produced by sudden occlusion of the circulation to the limbs with a pneumatic cuff for periods of up to 1.5 hours. During the first 10 min of occlusion, there was little change reaching about 25% of its control value after 40 min of arrest. On release of the circulation, lymph flow rose almost immediately to levels above the control value, resulting in a hyperlymphia whose size and duration was related to the duration of the circulatory arrest and the limb volume changes that followed. The results indicated that lymph flow can continue, albeit at reduced rates for long periods after circulatory arrest and that during reactive hyperaemia, there is a brisk hyperlymphia whose size and time course is similar to that of the limb volume changes.